White Spot Disease in Fish

Make sure you know how to diagnose white spot

Many people just starting an aquarium have problems with fish deaths. Even experienced aquarists have fish die on them without any apparent cause. It's very frustrating to go through the time and effort to carefully set up an aquarium and then have your residents get sick.

The main cause of fish death and the "white spot disease" is parasitic infection, internal or external. The visible signs that give white spot disease its name are little white dots on your fish's fins or main body. The parasite normally the cause for this is Ichthyophthirius Multifillis.

I. Multifillis has a free-swimming stage during which it attaches itself to fish. Infection results in visible white spots on the outside of the fish. The most common treatment is the chemical Methylene Blue. Usually about 1 milliliter of 1% solution is enough to treat a gallon of water and is good for a couple days. Ask your local pet shop's expert or a vet for advice.

You shouldn't leave Methylene Blue in your fish's water for an extended period, and remove activated charcoal filters as they filter out Methylene Blue. Dirt can absorb Methylene Blue, so use aeration with coarse bubbles near the surface or clean any dirt from the bottom before treatment.

White spot can cause behavior changes in fish as well--gasping at the surface, hovering in a corner, or staying at the bottom or surface continually can be signs of white spot. If you see your fish rubbing against rocks and being generally inactive, white spot is a possible suspect.

You can avoid frequent fish deaths with the proper treatment and by paying attention to how your fish are behaving in order to catch potential problems right away. Parasitic infection is a leading cause of fish deaths so be sure to consider it when trying to find a cause of fish problems.